First off, for transparency, Fosi Audio has graciously given me the unit for testing and reviewing purposes. My opinion and experience is my own, and I won't write anything I don't think is true or will I fluff my experience.
So... let's begin! I have to say that the presentation of the product is outstanding. Very nice finish, good size, heavy and solid, true to what Fosi audio usually delivers: compact, useful, pretty and simple. It would have been great to include a signature Fosi Audio orange knob to fit the styling of other amps. It fits with my V3 monos and my MC351's which I changed the knobs anyways, so all is good.
My unit came in the old Fosi boxes that are less refined than the boxes my V3 Monos shipped in, but a box is a box, I'm more interested in what's inside the box!
My audio tests were done with the Fosi V3 monos, two MC351 (each powering a woofer and a channel) and the Fosi T3 tube amp. My HT4S is used for another set of speakers and system, so I didn't test with it. All I can say is that to my ears, they all still sounded as good as they would even without the LC30 in between.
I'm not new to Fosi Audio, I've used their products since the beginning of the company, the first product I got from them was a small tube buffer/preamp. I still use it in another system... But as far as quality goes, let me tell you, boy have they evolved well! As such, yes, the LC30 is a fine product that looks as good as it feels when I'm handling it. Sturdy construction, none of that flimsy plastic or thin metal sheets. The front panel has useful and well spaced out buttons and knob configuration. My unit, with orange backlights, is stunning to look at, even my wife says it's nice looking.
Functionality:
The idea of going USB-C for power is both nice and an annoyance. I mean, it can be powered with easy to find parts, just a usb charger and you're done. Where I find it annoying is that I actually like good ol' 120v plugs. What I would suggest for Fosi is having a 12v USB-C output on a preamp fitting the LC30, to power it. Fosi could even make another straight dual mono (based on V3 mono, perhaps) power amp in the form factor of the LC30 that you could either stack on top or under. In any case, the USB-C is not a deal breaker in any way, it still works well and does what's expected.
One thing that I look for in audio products from a company is coherence, and the LC30 is coherent with other Fosi products, color and style wise. Thing is, if I could stack my 2 v3 monos on top as a single unit, with a preamp and dac built-in, I think I would just go crazy happy! Fosi, you *could* make such a product, allowing V3 mono owners to "transplant" their v3 monos (or ZA3) inside a case with a preamp and DAC. Just an idea/suggestion. Oh and it would allow EASY opamp rolling. One thing that would be cool is some kind of "cartridge" mechanism for easy changing opamp without opening devices, kinda like tubes. But I digress....
Feel:
The front has a nice knob for sensitivity, and you have buttons for selecting the amp or the speaker pair. Straightforward, no extras, it's what you need if like me, you're into the device because it can be used as a comparator. Now, I understand that the LC30 is a Power Meter, not just a VU meter, but I didn't have the reported issue about cranking up sensitivity for needles to move. "Regular" volume made the needles move, even if sensitivity isn't at maximum. Oh and, I have 2 kids sleeping upstairs, I never woke them up.
Sound wise, I found it transparent. I mean, it should be, it's basically a switching system. I used Fosi V3 monos as stated previously, which have plenty of power, I didn't find it to color the sound or deteriorate the signal. At the volumes I listen to, if the LC30 does lower the volume a bit, I can't hear it at all. I'd just raise the volume and not notice anyways. Some have reported that the LC30's needles need a crazy amount of power to move, my unit doesn't exhibit this whatsoever, I actually have to lower the sensitivity. After contacting Fosi directly, they have confirmed they have resolved the sensitivity issue for the updated model, which is what was sent to me. So if that "issue" stops you from buying one, it's not a reason anymore.
I find the unit just works perfectly as I had hoped it would. VU lights are nice and even, the leds are situated at the right place, the bottom. What I like best is that the unit is pretty neutral and doesn't scream its logo. I know it's from Fosi, the logo is not taking a lot of space, I find this a good design choice. I personally like humble embossed logos instead of printed logos, but if Fosi starts to emboss logos instead of printing, the price might go up. I can live with printed, if it's discrete.
Functions are what draws me to gear: does it do what it's supposed to do, does it do it well, could it be improved? Well, on that matter, it does what it should well: shows me levels, if signal is going through and allows me to switch amplifiers and speakers. It does so flawlessly. Could it be improved? Maybe, but as it is, I find it's complete. I got what I wanted and needed, I'm satisfied. It's simple to use, straightforward, it's what a VU meter should do. Some complain that it should have a volume control; I disagree. This is a VU unit and an AB comparator/switcher, not a preamp or an attenuator. Another box that would allow this and be assorted to the LC30 and fitting its design would be great.
What would I improve?
I'm sure Fosi will eventually make better and more intercompatible systems. One thing that COULD be made possible is keeping that design, but making it bigger. One thing I really like using in my setup is a Dynaco QD-1 for ambiance recovery for the back speakers. But it's always an extra box... It's a really simple circuit that could easily be integrated in a similar VU unit. Also, I would have it powered by a 48V 10A and allow for power distribution to 2 class D amps. That way only 1 brick could power amps and the VU. Finally, I would add a volume knob/attenuator that could be stepped, for each channel. It would then become part VU unit, part preamp, part power supply and part home theater... Just dreaming though..!
Would I recommend this product?
You can read between the lines of my review that this product is everything you'd expect from such a piece of gear. Nothing more, nothing less. It's not feature packed, which is great, in a way. For the price, you could get something similar from a competitor, but I find this model the best looking one, and to be honest, I like Fosi's customer service as it has been up to now. They have always been prompt in technical support and helpful with my questions.
As you read my reviews, you'll see that I'm an audio enthusiast, not a technician, so ratings and numbers, I don't do. I do have a technical background, but for this hobby, I trust my ears and my understanding of how a feature should be implemented and how gear serves my purposes.
The LC30 is a must own, for a person like me with many amplifiers and speakers. If it's something you'd need, just get one while it's still sold. Maybe in the future we'll get something similar, but different at the same time. In any case, Fosi is getting better and better, one awesome product at a time.